Acronym. Punch Him/Her In The Taint. If extremely upset with someone the word Punch can be replaced with Punt Him/Her In The Taint.

Uses: To be used when someone is being an annoying, whiny, high maintenance A-hole. It should be what you want to do to that person upon seeing the behavior and wanting to positively punish the negative behavior through PHITT behavior modification. Especially useful when athletes are not playing to their potential and need something more than a swift kick in the butt.

"That woman/guy is complaining about everything today, it makes me want to punch her in the teeth but instead I think he/she will understand my anger better if I P.H.I.T.T. 'em."

"If he/she doesn't start having fun on this adventure I am going to P.H.I.T.T. her right out of the car"